How to determine which service is consuming a lot of CPU time?

Question

Windows

Good day everyone! Available: Windows 8.1 x64
Faced a problem:
I began to notice that the svchost.exe process periodically eats a lot of CPU, instead of the task manager I use Process Hacker 2, I run it on behalf of SYSTEM using the psexec utility, so you can learn a lot more about processes than just running Process Hacker 2 even on behalf of the administrator, and in any case, much more than in general from the usual task manager,
and so. the svchost.exe process is not in the singular - I notice that from its running instances it loads the svchost CPU responsible for these services (the Services line):





I go to the process properties (Properties), in this case with PID 976, open the Threads tab and see the following:



Those. these two lines - ntdll.dll! RtlFreeUnicodeString+0x1370, at the very top, and periodically load the CPU up to almost 50%, and they are not connected with any services at all. I

went inside the top line and got the following content:


Here it is in the title already under another TID'om because TID constantly changes, came later - already TID another.
Further, knowledge does not allow to understand the essence of the problem, can someone tell me - what is the problem?
Maybe all the same, some of the above-mentioned services, on screenshots, are to blame for such a CPU load?

There are no viruses, the left software is not worth it, Windows Defender with all updates works

Answer 1

The solution is simple, here is a small example:

var a1,a2: array [1..10] of integer;
var b1,b2: array of integer;
a1 := a2; // копируется содержимое
b1 := b2; // копируется указатель

What's happening? And the fact that if you pass a static array to the procedure as a parameter in advance, you will get its contents, without the possibility of editing. Use dynamic arrays. The question is over!

Answer 2

Variables are passed through var as a pointer to a structure.
I think it needs to be like this:
procedure generateStartWord(var _grid: gridType);